"Analysis: Military sources say Pentagon’s assessment of Shujaiya shelling alarmed even Secretary of State John Kerry."

"11 Israeli artillery battalions — a minimum of 258 artillery pieces, according to the officer’s estimate — pumped at least 7,000 high explosive shells into the Gaza neighborhood, which included a barrage of some 4,800 shells during a seven-hour period at the height of the operation."

"The three Israeli units assaulting Shujaiya were never in danger of being defeated, but the losses the IDF suffered in the four-day house-to-house battle embarrassed IDF commanders. By the afternoon of July 19, even before Israel had suffered most of its casualties, the scale of resistance prompted Israeli battlefield commanders to blanket Shujaiya with high-explosive artillery rounds"

Such an overwhelming use of force however, creating difficulties within the context of urban warfare.

* You will never kill all the enemy combatants. Some will survive to fight another day.

* You will kill a lot of civilians and get a lot of bad press in the process.

* You create an urban landscape that is disadvantageous to further offensive operations but very advantageous to defensive operations.